The present invention relates to a solenoid operated fluid control valve having a solenoid assembly connected to a housing typically having one or more fluid bores of a fluid circuit.
A proportional variable force solenoid control valve that is relative low in cost to manufacture and compact in size while maintaining substantially linear proportional fluid control is described in the Najmolhoda U.S. Pat. No. 4,988,074 issued Jan. 29, 1991, of common assignee herewith. The patented proportional variable force solenoid control valve comprises an outer steel solenoid housing and an aluminum valve member housing joined together mechanically such as by tabs on the steel solenoid housing being crimped about regions of the aluminum valve member housing. The proportional variable force control valve includes a ferromagnetic (e.g. steel) armature suspended by low spring rate springs at opposite ends of the armature within the bore hole of a coreless solenoid bobbin for reciprocable movement between positions corresponding to a closed valve position and fully open valve position in response to applied electrical current to an electromagnetic coil. The position of the armature is controlled by balancing the variable force of an electromagnetic field of an electromagnetic coil and the force of the magnetic field of a permanent ring magnet against the force of a compression coil spring which biases the valve toward the closed position of the valve. The electromagnetic coil, bobbin and armature reside in the steel solenoid housing in a manner that the steel housing provides a concentration of flux of the electromagnetic field at the armature. The fluid control valve on the end of the armature moves relative to a valve seat disposed in the aluminum valve housing to communicate a fluid inlet to fluid exhaust ports so as to regulate fluid pressure at fluid control ports in a manner proportional to the magnitude of applied electrical current.
The Najmolhoda U.S. Pat. No. 5,611,370 issued Mar. 18, 1997, also describes a proportional variable force solenoid control valve that includes a substantially non-magnetic common housing for the solenoid and control valve, simplifying valve manufacture and construction while maintaining substantially linear proportional fluid pressure control.
An object of the present invention is to provide a solenoid operated fluid control valve having a twist-on, fluid tight solenoid connection to a housing having one or more fluid bores of a fluid circuit.
Another object of the present invention is to provide a solenoid assembly having features to provide a twist-on, fluid tight connection to a fluid circuit housing.
The present invention provides a solenoid operated fluid control valve connected to a fluid circuit housing having one or more fluid bores or passages by a twist-on, fluid tight connection between a solenoid assembly and the fluid circuit housing. In one embodiment, the fluid circuit housing includes a fluid bore and groove means disposed about the bore. A valve is disposed in the bore. A solenoid assembly is provided having an armature engaging the valve and movable in response to energization of a solenoid coil. The solenoid assembly includes a plurality of connection tabs axially confined in the groove means against fluid pressure in the fluid bore.
In a particular embodiment of the present invention, the fluid control valve includes a solenoid assembly having an armature movable in response to electrical current to a wire coil wound on a bobbin in a solenoid housing for controlling position of a fluid valve located in a valve body that is connected to the solenoid assembly. The valve body is received in a fluid bore of the fluid circuit housing and includes a compressible annular fluid seal disposed on region thereof that is received within the fluid bore to sealingly engage with the housing. The fluid control valve includes a plurality of connection tabs spaced peripherally apart and adapted to be initially received in entrances to groove means of the fluid housing. For example only, the solenoid coil bobbin and/or the valve body connected to the solenoid assembly includes the connection tabs. The fluid control valve is adapted to be connected to the fluid circuit housing by inserting the valve body therein in a manner to fluid tight compress the fluid seal with the connection tabs received in axial entrances to the groove means and then by turning or rotating the fluid control valve to angularly displace the connection tabs in the groove means to axially confined or trapped positions therein to hold the fluid control valve in the fluid bore when fluid pressure is present in the fluid bore. Rotary movement of the fluid control valve in the groove means is prevented by a connection between an electrical connector of the solenoid assembly and a lead frame which typically is affixed to the fluid circuit housing.